Medical physics aspects of cancer care in the Asia Pacific region: 2014 survey results.

It was the aim of this work to assess and track the workload, working conditions and professional recognition of radiation oncology medical physicists (ROMPs) in the Asia Pacific region over time. In this third survey since 2008, a structured questionnaire was mailed in 2014 to 22 senior medical physicists representing 23 countries. As in previous surveys the questionnaire covered seven themes: 1 education, training and professional certification, 2 staffing, 3 typical tasks, 4 professional organisations, 5 resources, 6 research and teaching, and 7 job satisfaction. The response rate of 100% is a result of performing a survey through a network, which allows easy follow-up. The replies cover 4841 ROMPs in 23 countries. Compared to 2008, the number of medical physicists in many countries has doubled. However, the number of experienced ROMPs compared to the overall workforce is still small, especially in low and middle income countries. The increase in staff is matched by a similar increase in the number of treatment units over the years. Furthermore, the number of countries using complex techniques (IMRT, IGRT) or installing high end equipment (tomotherapy, robotic linear accelerators) is increasing. Overall, ROMPs still feel generally overworked and the professional recognition, while varying widely, appears to be improving only slightly. Radiation oncology medical physics practice has not changed significantly over the last 6 years in the Asia Pacific Region even if the number of physicists and the number and complexity of treatment techniques and technologies have increased dramatically.

Medical physics aspects of cancer care in the Asia Pacific region: 2011 survey results.

BACKGROUND: Medical physicists are essential members of the radiation oncology team. Given the increasing complexity of radiotherapy delivery, it is important to ensure adequate training and staffing. The aim of the present study was to update a similar survey from 2008 and assess the situation of medical physicists in the large and diverse Asia Pacific region. METHODS: Between March and July 2011, a survey on profession and practice of radiation oncology medical physicists (ROMPs) in the Asia Pacific region was performed. The survey was sent to senior physicists in 22 countries. Replies were received from countries that collectively represent more than half of the world's population. The survey questions explored five areas: education, staffing, work patterns including research and teaching, resources available, and job satisfaction. RESULTS AND DISCUSSION: Compared to a data from a similar survey conducted three years ago, the number of medical physicists in participating countries increased by 29% on average. This increase is similar to the increase in the number of linear accelerators, showing that previously identified staff shortages have yet to be substantially addressed. This is also highlighted by the fact that most ROMPs are expected to work overtime often and without adequate compensation. While job satisfaction has stayed similar compared to the previous survey, expectations for education and training have increased somewhat. This is in line with a trend towards certification of ROMPs. CONCLUSION: As organisations such as the International Labour Organization (ILO) start to recognise medical physics as a profession, it is evident that despite some encouraging signs there is still a lot of work required towards establishing an adequately trained and resourced medical physics workforce in the Asia Pacific region.

A case of adult onset type II citrullinemia with portal-systemic shunt.

A 48-year-old woman who had conscious disturbance and abnormal behaviors had been misdiagnosed as having hepatic encephalopathy due to hyperammonemia and portal-systemic shunt, and retrograde transvenous obliteration of the shunt did not improve her symptoms. Thereafter, analyses of plasma amino acids and citrin gene revealed a diagnosis of adult onset type II citrullinemia (CTLN2). She underwent auxiliary partial orthotopic liver transplantation (APOLT) using a left lobe graft from her brother, and her symptoms as well as hyperammonemia improved. Our case demonstrates the importance of CTLN2 as a differential diagnosis in patients with hyperammonemia and consciousness disturbance, even if they present with a portal-systemic shunt.

The role, responsibilities and status of the clinical medical physicist in AFOMP.

This document is the first of a series of policy statements being issued by the Asia-Oceania Federation of Organizations for Medical Physics (AFOMP). The document was developed by the AFOMP Professional Development Committee (PDC) and was endorsed for official release by AFOMP Council in 2006. The main purpose of the document was to give guidance to AFOMP member organizations on the role and responsibilities of clinical medical physicists. A definition of clinical medical physicist has also been provided. This document discusses the following topics: professional aspects of education and training; responsibilities of the clinical medical physicist; status and organization of the clinical medical physics service and the need for clinical medical physics service.

Medical physics aspects of cancer care in the Asia Pacific region.

Medical physics plays an essential role in modern medicine. This is particularly evident in cancer care where medical physicists are involved in radiotherapy treatment planning and quality assurance as well as in imaging and radiation protection. Due to the large variety of tasks and interests, medical physics is often subdivided into specialties such as radiology, nuclear medicine and radiation oncology medical physics. However, even within their specialty, the role of radiation oncology medical physicists (ROMPs) is diverse and varies between different societies. Therefore, a questionnaire was sent to leading medical physicists in most countries/areas in the Asia/Pacific region to determine the education, role and status of medical physicists.Answers were received from 17 countries/areas representing nearly 2800 radiation oncology medical physicists. There was general agreement that medical physicists should have both academic (typically at MSc level) and clinical (typically at least 2 years) training. ROMPs spent most of their time working in radiotherapy treatment planning (average 17 hours per week); however radiation protection and engineering tasks were also common. Typically, only physicists in large centres are involved in research and teaching. Most respondents thought that the workload of physicists was high, with more than 500 patients per year per physicist, less than one ROMP per two oncologists being the norm, and on average, one megavoltage treatment unit per medical physicist.There was also a clear indication of increased complexity of technology in the region with many countries/areas reporting to have installed helical tomotherapy, IMRT (Intensity Modulated Radiation Therapy), IGRT (Image Guided Radiation Therapy), Gamma-knife and Cyber-knife units. This and the continued workload from brachytherapy will require growing expertise and numbers in the medical physics workforce. Addressing these needs will be an important challenge for the future.

Technology and its clinical application in the field of computer-assisted radiology and surgery.

The field of computer-assisted radiology and surgery involves a wide spectrum of topics based on medicine, physics, computer science and even sociology. The progress of development and recent trends in this field is described in this paper. Firstly, the chronological change in presented papers in past international conferences of Computer Assisted Radiology and Surgery (CARS) from 1985 to 2007 is illustrated in terms of topics, which are grouped into six main categories. Secondly, new directions and related topics are described by means of an example of a digital operating room. Problems in the operation room (OR) and solution concepts are pointed out while a therapy imaging and model management system (TIMMS) is presented as a possible solution. Finally, patient modelling related topics for CARS are listed.

Transgenic mice aberrantly expressing pyruvate dehydrogenase complex E2 component on biliary epithelial cells do not show primary biliary cirrhosis.

Primary biliary cirrhosis (PBC) is an autoimmune disorder that specifically destroys biliary epithelial cells (BECs). In patients with PBC, the immunodominant pyruvate dehydrogenase complex E2 component (PDC-E2), identified as an antigen for disease-specific anti-mitochondrial antibody, is expressed aberrantly in the BEC cytoplasm. The present study focused on the pathophysiological role of aberrant PDC-E2 in the development of PBC. The BEC-specific cytokeratin-19 promoter and PDC-E2 gene were cloned from a mouse cDNA library. The constructed transgene was microinjected into fertilized eggs of mice, and the offspring were identified by Southern blotting and reverse transcriptase-polymerase chain reaction. The protein expression was confirmed by immunoprecipitation, immunoblotting and immunohistochemical staining. Five founder lines were identified as carrying the PDC-E2 gene, and one of these lines expressed PDC-E2 mRNA. The protein expression of exogenous PDC-E2 was detected in the liver. The transgenic mouse line showed diffuse expression of PDC-E2 in the BEC cytoplasm. Biochemical, serological and histological features of PBC were not detected. We established transgenic mice that constitutively express PDC-E2. The results indicated that aberrant PDC-E2 expression in the cytoplasm of BECs is not sufficient for the initiation of autoimmunity. Additional factors may be required to establish a model of PBC.

An algorithm for mapping the catheter tip position on a fluorograph to the three-dimensional position in magnetic resonance angiography volume data.

This paper proposes an algorithm which maps the position of a catheter tip on a fluorograph to the 3D position in magnetic resonance angiography (MRA) data. This algorithm was assessed for its accuracy. We designed an algorithm consisting of a registration step and a recognition step. The registration step registers MRA and fluorography data using a digital subtraction angiography (DSA) image. The recognition step recognizes the position in the MRA data corresponding to the catheter tip position on a fluorograph. We checked the accuracy of the recognition step by employing an artificial data set consisting of 3D image data (64 x 64 x 64 matrix) and its projection image (92 x 92 matrix) and the accuracy of the registration step with the aid of three of the 3D time-of-flight MRA data sets (256 x 256 matrix and 60 slices) and their projection images in the form of DSA images. The accuracy of the recognition step depended upon that of the registration. When there was no misregistration, all of the mean errors were less than 0.2 mm. The mean errors of the registration step were 0.273 mm and 0.226 mm, respectively, for the longitudinal shift along the X and Y axes, 0.478 degrees, 1.203 degrees and 0.208 degrees, respectively, for the rotation angles around the X, Y and Z axes and 0.020 times for the magnification. The mean image error between the projection image of the registered MRA data and that of the MRA data which were employed as the DSA image was 0.034 mm.

Response to ADP-ribose by activation of TRPM2 in the CRI-G1 insulinoma cell line.

The response to intracellular ADP-ribose in the rat CRI-G1 insulinoma cell line was studied using a patch-clamp method. Dialysis of ADP-ribose into cells induced a response in a dose-dependent manner. The reversal potentials in various solutions showed that the ADP-ribose-gated channel was a Ca2+-permeable nonselective cation channel. In inside-out recordings, ADP-ribose and b-NAD induced responses in the same patch. The single-channel current-voltage relationships for ADP-ribose- and b-NAD-induced responses were almost identical, indicating that ADP-ribose and b-NAD activated the same channel. The physiological properties of the ADP-ribose-gated channel are similar to those we reported previously for the cloned transient receptor potential channel TRPM2. Moreover, RT-PCR analysis showed that TRPM2 was abundantly expressed in CRI-G1 cells, suggesting that the ADP-ribose-gated channel represents the native TRPM2 channel in CRI-G1 cells. These results suggest that ADP-ribose can be an endogenous modulator of Ca2+ influx through the TRPM2 channel into CRI-G1 cells.

Prognosis is predicted by early hearing improvement in patients with idiopathic sudden sensorineural hearing loss.

The time-course of the recovery of the hearing level after treatment in 90 patients with idiopathic sudden sensorineural hearing loss was examined. The improvement rate calculated relative to the hearing level of the opposite ear was investigated to estimate the hearing recovery. Follow-up audiograms were performed once per week for 1 month after treatment and once per month thereafter. There were two groups that differed with respect to the characteristics of hearing recovery. One group showed an improvement rate of over 50% at 1-2 weeks and a good improvement rate at 3 months after treatment. In the other group, the improvement rate did not reach 50% at 1-2 weeks, and the improvement rate was poor at 3 months after treatment. The patients with improvement rates of over 50% at 1-2 weeks had earlier initial visits and had mild hearing loss, whereas the patients with profound hearing loss had improvement rates under 50% and poor long-term prognosis. We conclude that the improvement rate at 1-2 weeks after treatment predicts the long-term prognosis for recovery of hearing level in patients with sudden sensorineural hearing loss.

PACS linked to EPR.

We developed a new PACS linked to Electronic Patient Record system (EPR). It was a hospital-wide PACS storing all the radiological examinations. The images and reports were linked on EPR. The concept of navigation servers and segment servers was introduced for prefetchig and quick displaying. After the start of operation, increasing retrieval indicated its effectiveness on practical work in spite of remaining delivery of radiographs.

Cloning and characterization of the 5'-flanking region of human cytokeratin 19 gene in human cholangiocarcinoma cell line.

BACKGROUND/AIMS: The regulatory mechanism of cell-specific gene expression in cholangiocytes has not been sufficiently evaluated. In this study, we characterized the 5'-flanking region of the cytokeratin 19 gene expressed specifically in cholangiocytes. METHODS: We cloned a 2952-bp fragment in the 5'-flanking region of cytokeratin 19 and evaluated the regulatory mechanism of gene expression in this region by assaying transient expression of reporter gene and DNA footprinting. RESULTS: This segment of the 5'-flanking region of the human cytokeratin 19 gene shows an intense transcriptional activity in the cholangioma cell line KMBC, which was about 10 times its activity in the osteosarcoma cell line Saos-2, which does not express cytokeratin 19. From the results of reporter assays, important transcription regulatory elements are considered to be located in the segments from -2249 to -2050 bp and from -732 bp to the first ATG, and six protein-binding sites were detected in the segment from -732 bp to the first ATG by the DNA footprinting technique. CONCLUSIONS: Sp1 site, CCAAT box, and TATA box were present in the segment from -374 to the first ATG, and they are considered to constitute a cholangiocyte-specific promoter.

Immunocyte Ca2+ influx system mediated by LTRPC2.

We characterized an activation mechanism of the human LTRPC2 protein, a member of the transient receptor potential family of ion channels, and demonstrated that LTRPC2 mediates Ca2+ influx into immunocytes. Intracellular pyrimidine nucleotides, adenosine 5'-diphosphoribose (ADPR), and nicotinamide adenine dinucleotide (NAD), directly activated LTRPC2, which functioned as a Ca2+-permeable nonselective cation channel and enabled Ca2+ influx into cells. This activation was suppressed by intracellular adenosine triphosphate. These results reveal that ADPR and NAD act as intracellular messengers and may have an important role in Ca2+ influx by activating LTRPC2 in immunocytes.

Status of PACS and technology assessment in Japan.

The situation of PACS installations in Japan from 1987 to 1999 has been investigated. By 1999, 751 PACS units have been installed. Of these, 613 are small-size PACS with less than four image display terminals, 96 are medium-size with 5-14 terminals and 42 are large-size with 15 up to 300 terminals. The 42 hospitals with large sized PACS have been retrospectively investigated from 1984 for PACS experiments and from 1989 for PACS operation. Most of these 42 hospitals have increased the number of PACS terminals by installing additional PACS units instead of reinforcing the existing single PACS. Some (23%) PACS installations have obviously not been successful because of low image transfer speed and inadequate image quality. The use of DICOMM interfaces has increased the number of modalities connected to PACS and influenced the spread of PACS installations in Japan. The status of HIS and RIS coupling to PACS and the use of PACS in primary diagnosis or in image referral are discussed. Assessment of PACS is now in a very early stage. Baseline studies of HIS/RIS/PACS effectiveness have been carried out to assess quantitatively the PACS merit. Radiologists' answers to the questionnaire on PACS usage do not fully support the finding that the number of PACS installations is growing in Japan.

Detection of subtle pulmonary disease on CR chest images: monochromatic CRT monitor vs color CRT monitor.

To clarify the diagnostic efficacy of color soft-copy computed radiographic (CR) images of the chest in the detection of subtle pulmonary abnormalities. Twenty observers compared 87 soft-copy CR images on four types of CRT monitor (nonmagnified monochromatic CRT, magnified monochromatic CRT, nonmagnified color CRT, and magnified color CRT). Of 87 test images, 45 (including two identical sets of 12 images to test intraobserver variability) were abnormal and 42 (including two identical sets of 12 images) were normal. Of the 45 abnormal images, 15 showed subtle abnormalities, 15 showed mild abnormalities, and 15 showed obvious abnormalities. In the receiver operating characteristic (ROC) analyses, there were no statistically significant differences among the four types of CRT display formats in the detection of subtle abnormalities. Color CRT monitors can replace monochromatic CRT monitors without any loss in the ability to detect subtle interstitial lung disease.

The effects of erythromycin on human peripheral neutrophil apoptosis.

Erythromycin is reported to have an anti-inflammatory action, which may account for its clinical effectiveness in treating chronic inflammatory diseases of the respiratory tract such as diffuse panbronchiolitis (DPB) and chronic sinusitis. The evaluate the anti-inflammatory action of erythromycin, we examined apoptosis of isolated neutrophils incubated with and without erythromycin. As a result, erythromycin augmented neutrophil apoptosis in a dose-dependent manner, with a maximal effect at 10 micrograms/ml and above. The percentage of neutrophil apoptosis at 12 h was 79.2 +/- 2.3% in medium with 10 micrograms/ml of erythromycin compared with 51.2 +/- 4.1% in control medium (p < 0.005). In a manner similar to that of erythromycin, another macrolide antibiotic, roxithromycin, also increased neutrophil apoptosis. However, there was no effect on apoptosis induced by treatment with josamycin (macrolide antibiotic), ampicillin (beta-lactam.) and cefazolin (cephalosporin antibiotic), or gentamycin (aminoglycoside). These findings suggest that erythromycin shortens neutrophil survival by accelerating neutrophil apoptosis.

Inward current responses to urinary substances in rat vomeronasal sensory neurons.

No study has yet demonstrated an inward current in response to pheromonal substances in vomeronasal sensory neurons. Using female rat vomeronasal sensory neurons, we here successfully recorded inward currents in response to urine from various sources. Of the neurons that responded to urine, 77% responded to only one type of urine. Male Wistar urine induced responses preferentially in the apical layer of the sensory epithelium, whilst male Donryu and female Wistar urine induced responses mainly in the basal layer of the epithelium. The amplitude of inward currents induced by application of male Wistar urine was voltage-dependent with average amplitude of -47.1+/-6.2 pA at -74 mV. The average reversal potential for male Wistar urine was -9.3 +/-6.1 mV, which was not apparently different from the reversal potentials for urine from different species. It is likely that the urine-induced inward currents in response to different types of urine are mediated via a similar channel. The simultaneous removal of Na+ and Ca2+ from extracellular solution eliminated the response. The magnitude of the urine-induced inward current in Cl--free external solution was similar to that in normal solution, suggesting that the urine-induced current is cation selective. Removal of external Ca2+ enhanced the amplitude of the urine-induced current and prolonged the response. Application of the constant-field equation indicated a very high permeability coefficient for Ca2+. This study first demonstrated that substances contained in urine elicited inward currents, which induce an excitatory response in vomeronasal sensory neurons, through cation-selective channels.

Inhibition of fos-immunoreactivity in response to urinary pheromones by beta-adrenergic and serotonergic antagonists in the rat accessory olfactory bulb.

The vomeronasal organs of female Wistar rats after the intraperitoneal administration of ketanserin and propranolol prior to sacrifice were exposed to sprayed urine of male Wistar rats. To explore the effects of these antagonists, we studied Fos-immunoreactive (Fos-ir) structures, which correlate with cellular activity, in the accessory olfactory bulb of female rats after the vomeronasal organ was exposed to urine. After the administration of 3 mg/kg ketanserin, the expression of Fos-ir cells in the periglomerular cell layer in response to male Wistar urine was inhibited, while that in the mitral/tufted cell and granule cell layers was not changed. The administration of 20 mg/kg propranolol inhibited the expression of Fos-ir cells in all three layers. These results suggest that serotonin and noradrenaline are likely involved in the modulation of the expression of Fos-ir cells in response to the urine in the accessory olfactory bulb.

Increases in Fos-immunoreactivity after exposure to a combination of two male urinary components in the accessory olfactory bulb of the female rat.

Exposure to either the dialyzed urine preparation (<500 Da) or the remaining substances (>500 Da) did not induce expression of Fos-immunoreactive cells in the mitral/tufted cell layer of the accessory olfactory bulb (AOB), whereas exposure to a mixture of these preparation did induce expression. These results suggest that a combination of low and high molecular weight substances is necessary for the increases in Fos-immunoreactivity in the AOB.